converter

sealed class Measure(
        val short: String,
        val normal: String,
        val plural: String,
        val multiplier: Double,
        val shift: Double = 0.0
)

class Dist(
        short: String,
        normal: String,
        plural: String,
        multiplier: Double
) : Measure(short, normal, plural, multiplier)

class Weight(
        short: String,
        normal: String,
        plural: String,
        multiplier: Double
) : Measure(short, normal, plural, multiplier)

class Tempr(
        short: String,
        normal: String,
        plural: String,
        multiplier: Double,
        shift: Double
) : Measure(short, normal, plural, multiplier, shift)

val allMeasures = listOf(
        Dist("a", "a", "a", 1.0),
        Weight("b", "b", "b", 2.0),

        Tempr("degree", "c", "", 1.0, 0.0),
        Tempr("fahrenheit", "f", "", 1.8, 32.0),
        Tempr("kelvin", "k", "", 1.0, 273.5)
)

val nameToMeasure = allMeasures
        .flatMap { m ->
            listOf(m.short, m.normal, m.plural).map { name -> name to m }
        }.toMap()


fun main(args: Array<String>) {
    // 23 f to k

    val m1 = nameToMeasure.getValue("f")
    val m2 = nameToMeasure.getValue("k")
    val input = 23

    if (m1::class != m2::class) {
        throw IllegalStateException("incomparable types: ${m1::class.simpleName} and ${m2::class.simpleName}")
    }

    val inDefault = (input - m1.shift) / m1.multiplier

    val output = inDefault * m2.multiplier + m2.shift
    println(output)
}